feat: item

Author: gadomski

src/pystac/item.py

@@ -142,9 +142,9 @@ def get_assets(
         )
 
     def make_asset_hrefs_relative(self) -> None:
-        if self_href := self.get_self_href():
-            for asset in self.assets.values():
-                pass
+        if self.get_self_href():
+            # TODO actually implement
+            pass
         else:
             raise ValueError(
                 "Cannot make asset hrefs relative, item does not have a self href"
@@ -170,6 +170,8 @@ def get_collection(self) -> Collection | None:
             # TODO can we just make get_target just take a STACObject?
             stac_object = collection_link.get_target(self.get_self_href(), self.reader)
             if isinstance(stac_object, Collection):
+                if root := self.get_root():
+                    stac_object.set_root(root)
                 self._collection = stac_object
                 return stac_object
             else:
@@ -195,6 +197,7 @@ def collection_id(self) -> str | None:
 
     def set_collection(self, collection: Collection | str | None) -> None:
         self._collection = collection
+        self.remove_links("collection")
 
     @override
     def to_dict(